Startup.cmd:

powershell -command “set-executionpolicy Unrestricted” >> out.txt

Windows Azure Role OnStart

The OnStart method of your WebRole class executes after IIS has been set up by the fabric, so at this time we’re free to run scripts that make the required configuration changes. The first thing to note is that normally the OnStart method does not run with administrator privileges—we’ll need to change this for our script to work.

ServiceDefinition.csdef:

    …

    <Runtime executionContext=“elevated” />

Now, we can add the code that kicks off our PowerShell script when the role starts:

WebRole.cs:

    public class WebRole : RoleEntryPoint

    {

        public override bool OnStart()

        {

            var startInfo = new ProcessStartInfo()

            {

                FileName = “powershell.exe”,

                Arguments = @”.setuprolestart.ps1″,

                RedirectStandardOutput = true,

                UseShellExecute=false,

            };

            var writer = new StreamWriter(“out.txt”);

            var process = Process.Start(startInfo);

            process.WaitForExit();

            writer.Write(process.StandardOutput.ReadToEnd());

            writer.Close();

            return base.OnStart();

        }

    }

Finally, we come to the PowerShell script that starts the listener service and configures the bindings. There are a few things to note about this script:

• If you’re using TCP instead of Named Pipes, change all references to net.pipe to net.tcp, change the bindings to include your chosen port (e.g. “808:*”). You’ll also need to enable and both the NetTcpPortSharing and NetTcpActivator services.
• The script makes some assumptions on the name of your role and also updates the protocols on all IIS virtual applications. Depending on how you’ve set up your roles and sites you may need to change this.
• There are some differences in how you access the IIS PowerShell cmdlets between IIS 7.0 and IIS 7.5. My script works for IIS 7.5, which is included in Windows Server 2008 R2 and the “2.x” family of the Windows Azure OS. To get this version, make sure you set osFamily=”2″ in the root node of your ServiceConfiguration.cscfg file. Alternatively if you want to use IIS 7.0 (Azure OS “1.x”) you can modify your PowerShell script to make this work.

RoleStart.ps1:

write-host “Begin RoleStart.ps1”

import-module WebAdministration

# Starting the net.pipe service

$listenerService = Get-WmiObject win32_service -filter “name=’NetPipeActivator'”

$listenerService.ChangeStartMode(“Manual”)

$listenerService.StartService()

# Enable net.pipe bindings

$WebRoleSite = (Get-WebSite “*webrole*”).Name

Get-WebApplication -Site $WebRoleSite | Foreach-Object { $site = “IIS:/Sites/$WebRoleSite” + $_.path; Set-ItemProperty $site -Name EnabledProtocols ‘http,net.pipe’}

New-ItemProperty “IIS:/Sites/$WebRoleSite” -name bindings -value @{protocol=”net.pipe”;bindingInformation=”*”}

write-host “End RoleStart.ps1”

Summary

With the right elements in your Windows Azure Service Definition and Service Configuration files, most common configuration tasks can be achieved without any coding or scripting. However there are some useful capabilities that you may be used to from on-premises Windows installations that are not currently exposed in this way. Fortunately, if you’re familiar with scripting techniques and the Windows Azure startup sequence you can normally code your way around these problems. Windows Process Activation Services is one example of a useful feature that’s not obviously available in Windows Azure, but can be made to work with a little perseverance. 

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